The notoriously secretive company makes a surprising new commitment to transparency, identifying 97 percent of its supply chain and shaming factories that test workers for pregnancy or use child labor.

Seeking to stave off criticism about working conditions at manufacturing plants, Apple Inc today identified 156 of its major suppliers and gave a detailed report on factory inspections, according to The Wall Street Journal.

The company likewise pledged to address worker abuses in is supply chain, which is largely within Asia.

Apple's report said it had found that problems persisted in matters such as hazardous waste handling, overtime pay and working hours. Apple said that only 38 percent of the time were suppliers complying with a maximum 60 hour work-week, according to The Journal.

The companies identified in today's report are responsible for 97 percent of Apple's spending on materials and packaging. The report found that 108 companies didn't pay proper overtime and that records at 93 facilities showed that more than half of workers exceeded the 60-hour work week. Five factories used child labor, according to The Journal.

The Journal also said 24 facilities conducted worker pregnancy tests and 56 had no policy in place to prevent discrimination against pregnant women; 112 facilities did not properly store or transport hazardous materials and 69 did not dispose of it properly.

Tim Cook, Apple's new chief executive, told The Journal that was taking serious steps to address such problems, such as doubling the number of its supplier audits.

"I have spent a lot of time in factories over my lifetime and we are clearly leading in this area," Cook was quoted as saying. "It is like innovating in products. You can focus on things that are barriers or you can focus on scaling the wall or redefining the problem."

The Reuters news agency called the step "dramatic and unprecedented" and all-the-more unexpected given Apple's secretive nature.

Apple's share price closed down at $419.81 today, a 0.37 percent drop, or a loss of $1.58, on the previous day's close.

According the The Journal, Apple has become the first technology company to join the Fair Labor Association, a non-profit labor standards organization, which exposes the company to independent monitoring.